Looking for a 12v trigger transmitter & receiver

[win]

I have programmed the smart plug to work with my Logitech harmony remote

good idea!

glad it worked out

 

[catalogguy]

I am in something of a similar boat and, after reading this thread and the linked articles and products, I think I would like to build an IR-controlled switch for a trigger output. The result would be a little box that, upon receiving a signal from the Logitech Harmony remote, will send current to the trigger input on the amp. Could someone please recommend an appropriate component? I have a couple of wish-list attributes.

1. The amp trigger input will accept 5 volts. I would like to connect a USB power source to the switch in order to both power the operation of the switch and pass the current through to the amp.

2. Allow a remote IR receiver on a wire to be plugged into the switch, so I do not have to ensure that the box remains properly positioned to receive the IR signal from the Harmony remote.

 

[win]

Even if the switch operated with a 5v trigger, I would think you would still want it to output 12v.

The simplest way would be to have your harmony control a smart plug with a 12v switch mode power supply plugged into it. This can turn on and off a 12v source with your harmony remote positioned anywhere, since it would be WiFi controlled not IR. Then you modify the power supply to have a 1/4" mono TR plug, and tee off of that for any additional components you'd like to trigger on and off.

 

[kevin1969]

I think this is what you're looking for

https://emotiva.com/products/et-3

 

[Dundas]

There are lot more of these available on eBay:
https://www.amazon.com/dp/B07NSG2XSN
This is 12V one:
https://www.amazon.com/dp/B07QH6XP9P/
The 2 key ones have discrete ON and OFF IR codes.
There are also versions that have learning capability so you can use IR codes of your own choosing.

 

[jeremya]

Apologies for the thread necromancy, but I happen to be on the hunt for the same thing as the OP.

TL;DR: I want a wireless 12v transceiver pair such that I can plug in a standard 3.5mm TR (mono) trigger cable and when it detects the incoming voltage, it sends some signal to a paired receiver that outputs 12v to a different trigger wire into the target device. Thus, the devices can be galvanically isolated, yet one still triggers the other.

Lengthy context:

I have an AVR (Marantz SR8015) that sends L/R audio out via RCA to a McIntosh C75 pre-amplifier which in turn sends it to a pair of Hypex Nilai500 monoblocks I built recently. My B&W 803 mains sound much better when the signal is amplified by the Hypex amps and handled via the McIntosh than when they are directly driven by the Marantz (even in a bi-amp + bi-wire configuration), hence my desire to use them in this way.

Essentially, I have two systems (a dedicated 2-channel listening system, and a home theater system) in one rack sharing one pair of speakers, and I got tired of moving the speaker cables back and forth every time I (or my family) wanted to change the active system.

Unfortunately, the system has a tendency to inject some really strange noise when in this 'passthru' configuration, and I've been doing a lot of work to eliminate it. I've reduced the matrix down to this set of things where the noise is apparent:

TV <- HDMI -> Marantz <- RCA L/R + 12v trigger cable -> McIntosh <- XLR -> Hypex Amplifiers < speaker cables > Speakers

When all of these are on, the noise is present. Note: all of these are / can be plugged into the same circuit (I've tested a lot of configurations... and this is a non-starter for me, as I really want the Marantz to pass through a clean audio signal to the McIntosh. It's designed to receive one, even featuring a discrete 'passthru' mode that has its own 12v trigger to toggle it).

When the HDMI is disconnected, the noise goes away. (If I but touch the shield of the HDMI to any HDMI port on the TV, the noise returns.)

Similarly, if I just play (whatever source, e.g. our Apple TV) through the Marantz and use it to power the speakers (cutting the McIntosh and the Hypex amps out of the loop) the noise goes away.

To try and see if it was as specific piece of gear that was the trouble (like the TV, which is an old plasma TV), I tried substituting an LCD monitor I had lying around. No change.

I've also tried removing extraneous connections (such as trigger wires) between the Marantz and the McIntosh. No change. I suspect this is because the noise is flowing through the RCA grounds.

To test the RCA ground transmission theory, I've got a Jensen CI-2RR stereo RCA isolation transformer on order. I've also considered something like the SVS SoundPath Tri-Band Wireless Audio Adapter and may yet go that route.

Should that prove effective, I'm still going to need to trigger my McIntosh to initiate pass-thru mode whenever the Marantz receiver is turned on (i.e., the family wants to watch TV, not listen to music) in a way that is galvanically isolated. That means I need an automatic, wireless 12V trigger transciever pair.

I'm happy to DIY something if need be, so long as it isn't crazy complicated, but I'd like to throw a pre-made solution at it if one exists...

 

[catalogguy]

There are a number of gizmos available that may help. Please confirm that you wish to control the pre-amp when then AVR is powered on?

Does the AVR have a trigger output?
Does the pre-amp have a trigger input?
Do you use a programmable remote to which you could add a device to control the 12v power for the trigger?

 

[JustJones]

Might try something like this on the 12v trigger wire.

https://www.amazon.com/dp/B019FC6ZQQ/ref=syn_sd_onsite_desktop_0?ie=UTF8&psc=1&pd_rd_plhdr=t

 

[jeremya]

There are a number of gizmos available that may help. Please confirm that you wish to control the pre-amp when then AVR is powered on?

Correct. Desired state behavior:

AVR on ==> Pre-amp on and triggered into 'passthru' mode.

AVR off ==> Pre-amp resumes whatever it was doing before (either powered off, or if it was on already, it reverts to the previous input).

All the above "smarts" are built into the McIntosh C75. You tell it what input is the 'passthru' and it auto-switches when +12v is seen on the trigger port.

Does the AVR have a trigger output?

Yes. I'm currently using it.

Does the pre-amp have a trigger input?

Yes. I'm currently using it.

Do you use a programmable remote to which you could add a device to control the 12v power for the trigger?

No, and I have no desire to. (Well, I might not mind using one by my wife... no. She only likes the Apple TV remote and it uses CEC to control All The Things(tm). I can scarcely get her to use the Apple TV remote app on her phone when the remote gets misplaced).

For WAF reasons, this needs to be fully automated such that the very act of powering on the receiver causes the trigger to tell the transmitter to trigger the pre-amp, and then when the AVR is turned off, the trigger is disabled. Essentially, I want to replicate my currently wired scenario but in a wireless (or at least galvanically isolated) manner. It has to "just work" or the spousal frustration level ratchets upwards.

Something like a Jensen isolation transformer that I plug a pair of trigger wires into (one input, one output) could work, but it's needs to be 12v.

 

[jeremya]

Might try something like this on the 12v trigger wire.

https://www.amazon.com/dp/B019FC6ZQQ/ref=syn_sd_onsite_desktop_0?ie=UTF8&psc=1&pd_rd_plhdr=t

Nice find! Something like that may do the trick. No telling if that will tolerate 12v, though. Also, it should have mono (TS) jacks, not TRS jacks. Depending on where the internal connector is, a stereo jack might cause problems of its own (according to everyone I've spoken to today -- they all suggested I make sure I'm using a mono trigger wire, not a stereo one!)

 

[jeremya]

This bad boy might work. Probably overkill (not sure how much they cost)... https://www.jensen-transformers.com/product/ci-2mini/

[edit]: somehow this one is even more expensive than the RCA stereo model. I'm seeing prices upwards of $260+. That's crazy!

 

[sam_adams]

This bad boy might work. Probably overkill (not sure how much they cost)... https://www.jensen-transformers.com/product/ci-2mini/

[edit]: somehow this one is even more expensive than the RCA stereo model. I'm seeing prices upwards of $260+. That's crazy!

That's an audio signal transformer designed to isolate the connected devices to eliminate ground loops. It is not designed for a 12VDC trigger application.

 

[catalogguy]

If you only need the trigger to provide power during your own sessions, perhaps you could introduce a new, isolated source of power. See reference to a gizmo with its own remote: ASR post

Amazon link

 

[jeremya]

That's an audio signal transformer designed to isolate the connected devices to eliminate ground loops. It is not designed for a 12VDC trigger application.

Yes and yes. The only reason I brought it up is that their spec sheet say it might stand up to a 12V signal with aplomb, unlike cheaper variants. Even so, I wouldn’t put that much money into a trigger solution. Shouldn’t be anywhere near that expensive. I don’t need fidelity, I just need reliable application (and cessation) of 12VDC with complete galvanic isolation.

 

[jeremya]

If you only need the trigger to provide power during your own sessions, perhaps you could introduce a new, isolated source of power. See reference to a gizmo with its own remote: ASR post

Amazon link

Unfortunately, I need it to work during *my wife’s sessions* which is primarily Home Theater / TV. And as mentioned before, that means it needs to “just work” and work automatically (no special remote, no troubleshooting mysterious failures, etc.)

 

[catalogguy]

The new topping E70 dac has a trigger output and they say the dac wakes up from any input. It would be isolated from the avr if connected by optical cable.

 

[jeremya]

The new topping E70 dac has a trigger output and they say the dac wakes up from any input. It would be isolated from the avr if connected by optical cable.

Clever!

It’s also $350 which is a bit beyond my price target for a trigger

I might need to homebrew something…

 

[catalogguy]

There are smart power strips, if that’s safe for your pre-amp.
Amazon link

 

[Doodski]

There are smart power strips, if that’s safe for your pre-amp.
Amazon link

Part of the link is missing and the link is a dead end.

 

[catalogguy]

Ooops trying again
https://www.amazon.com/SCG-3MVR-Sma...c-4019-bf5d-a85633001c08&ref_=pd_gw_ci_mcx_mi